He added that the other two probable new cases came in Bartow County, in the northwest corner of metro Atlanta.

"We're working with the GBI and other agencies to confirm four more cases," said Department of Public Health spokesman Ryan Deal on Friday.

Public Health said that eight Brunswick cases appear to be from "Crazy Clown," which has been marketed as herbal incense, bath salts, or roll-your-own tobacco.

A week ago, Public Health sent out an emergency alert to doctors and physician assistants about the substance, which has been sold in convenience stores and other shops. Allen credited the Georgia health officials for "doing a great job getting the word out."

The GBI Crime Lab is close to identifying the ingredients in the substance inhaled or ingested in the Brunswick area, Allen said.

He said Georgia officials have been in contact with health officials in Denver, where metro area emergency rooms are seeing a surge of patients agitated and violent after using synthetic marijuana.

When ingested or inhaled, the neurotoxin in the drug can render a person immobile or unconscious and cause severe cardiac problems.

Public Health officials said first responders have reported unusual strength, agitation and combativeness in some users. Others have been rendered immobile, displayed abnormal reflexes or no reflexes at all, and in some cases lost consciousness.

Symptoms may appear almost immediately after a person ingests or inhales the substance, or the symptoms may be delayed until more of the product is taken in.

Allen said Brunswick area merchants are removing the products from their stores.

The state has attempted crackdowns on synthetic marijuana and herbal incense in the past, and last year Gov. Nathan Deal signed a law prohibiting "all forms of synthetic marijuana."

But some manufacturers change the composition of these products slightly to try to get around the wording of the law and keep the products on store shelves.